1. Field of the Invention
The field of this invention relates to a method, disk array, and rebuilding process to rebuild a failed disk in a disk array.
2. Description of the Related Art
In disk arrays that are configured according to standards such as Redundant Array of Independent Disks (“RAID”) 5, when a disk gets rejected, a rebuild takes place using a spare disk to rebuild the data. The rejected drive is commonly bypassed by the disk array, as a failed disk can cause network issues that can affect access to all of the other disks in the array. During a rebuild, in for example, five or ten disk arrays, the disk array system is exposed to medium errors on other disks within the disk array, which will result in sectors in the failed disk being lost (creating kill sectors in that disk). This is the most common form of data loss, and the likelihood of such a data loss occurring increases as the number of disks in the disk array increases, and through the use of low cost disk drives in a server environment. At the present time, one resolution of the problem is to move the disk array system to RAID 6, but this is a more expensive solution, and is not always appropriate in every instance.
It is therefore an object of the invention to improve upon the known art for rebuilding a failed disk in a disk array.